Improving methods for preventing diseases of pasture grasses and securing the quality of feedstuff

The potential quality of the 6 pasture grasses Setaria sphacelata var. sericea cvv. Nandi, Kazungula and Narok and var. splendida, Digitaria eriantha ssp. pentzii (pangola grass), and Pennisetum clandestinum cv. Whittet (kikuyu grass) was assessed in terms of liveweight gain of beef cattle, using a leader and follower grazing system. Pasture management was designed to provide adequate quantities of young leaf to the leaders throughout the year. This was achieved by rotational grazing and weekly adjustment of the number of followers, depending on quantity of feed available. Annual liveweight gain of the leaders (kg/steer.year) ranged from 135 (kikuyu grass) to 159 (cv. Narok) (540-636 kg/ha.year). Differences between grasses on an annual basis and over summer were not statistically significant (P = 0.12), although significant differences in liveweight gain of leaders - - - were obtained during the winter. This was associated with differences between grasses in growth at lower temperatures, and in frost tolerance. Liveweight gain of the follower group was markedly higher for pangola grass and var. splendida (272 kg/ha.year) than for the other varieties (77-140 kg/ha.year). This difference was associated with differences in number of grazing days and in the superior liveweight gain per head of followers grazing pangola grass and splendida. Liveweight gain of leaders per annum was comparable for years 1 and 2 but fell dramatically from February to August in year 3. This was associated with high rainfall, reduced solar radiation, and a decrease in in vitro digestibility of plucked leaf of all setaria varieties but not of pangola or kikuyu grasses. The relatively low liveweight gains obtained in year 3 were not associated with any overall mineral or protein deficiency.

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Effect of surface application of benzylaminopurine before and during water deficit on herbage production and quality

Australian Journal of Experimental Agriculture ◽

10.1071/ea07075 ◽

2008 ◽

Vol 48 (9) ◽

pp. 1232

Author(s):

J. M. Lee ◽

K. Elborough ◽

D. Whittaker ◽

D. J. Donaghy ◽

J. R. Roche

Keyword(s):

Water Deficit ◽

Perennial Ryegrass ◽

White Clover ◽

Water Availability ◽

Plant Tolerance ◽

Nitrogen Fertiliser ◽

Pasture Grasses ◽

Herbage Quality ◽

Effect Of Surface

Insufficient water availability is one of the most serious environmental stresses for a plant and can be a major limitation to herbage production in many regions. Plant hormones, such as cytokinins, have been reported to reduce the detrimental effects of low water availability in many different plant species. However, there is little research available concerning the effect on pasture grasses. The aim of the present study was to quantify the effect of surface applications of 6-benzylaminopurine (BAP) before and during water deficit on herbage growth and quality of perennial ryegrass–white clover pastures. Pastures fertilised with BAP were compared with unfertilised pastures and pastures receiving nitrogen. Exogenous BAP application did not significantly affect herbage production or quality relative to unfertilised pastures. Nitrogen fertiliser increased total herbage production, but had little effect on herbage quality compared with BAP. The failure of surface applications of exogenous BAP to improve herbage production or quality suggests that it is not an appropriate method to enhance plant tolerance to water deficit at the concentration applied in this study.

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THE EFFECT OF TIME OF INITIAL CUTTING ON FORAGE YIELD AND QUALITY OF THREE PASTURE GRASSES AT SHIKA, NIGERIA

Nigerian Journal of Animal Production ◽

10.51791/njap.v26i1.3032 ◽

2021 ◽

Vol 26 ◽

pp. 93-97

Author(s):

O. S. Onifade ◽

A. M. Adamu ◽

E. C. Agishi

Keyword(s):

Dry Matter ◽

Nutritive Value ◽

Forage Yield ◽

Panicum Maximum ◽

Brachiaria Decumbens ◽

Yield And Quality ◽

June July August ◽

Pasture Grasses ◽

June July

The effect of time of cutting on yield and nutritive value of three year old pastures of signal (Brachiaria decumbens), green panic (Panicum maximum var. trichoglume) and buffel (Cenchrus ciliaris ev. Gayndah) grasses were studied. The pastures were harvested for hay yield on 5th November, 1977 and allowed to rest until subjection to initial cut in June, July, August or September, 1978. Immediately after the July cut, all the plots received 100kg N/ha and 40kg P205/ha. Regrowths from the initial cuts and the control (uninterrupted growth) were all cut on 16th November, 1978. The dry matter (DM) yields of the grasses increased with increasing stage of maturity. Signal grass was more productive (P < 0.05) (17.3t/ha) than the other grasses averaged over the cutting dates. The yields of green panic and buffel grasses were 8.3 and 11.0t/ha respectively. The regrowth DM yields declined with a delay in the initial cut. Except for the increases in CP (6.9%) and IVDMD (50.1%) contents of the primary growth in August, these parameters declined as the grasses aged. Deferring the initial cutting date resulted in significant (P < 0.05) increases in CP and IVDMD contents of the regrowths. Percent increases as a result of cutting at the different date over the control for DM and CP yield were 28 and 74, respectively. Further evaluation of the three species in grazing trial is suggested.

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NUTRITIVE VALUE AND PERENNIALITY 0F PASTURE GRASSES

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1970.32.1292 ◽

1970 ◽

pp. 76-86

Author(s):

R.J. Clements

Keyword(s):

New Zealand ◽

Nutritive Value ◽

Special Importance ◽

Perennial Species ◽

Annual Species ◽

Plant Survival ◽

Pasture Grasses ◽

Herbage Quality

In the genera Phalaris and Lolium, annual species have higher herbage nutritive value than perennials, and hybrids between annuals and perennials are intermediate. It is not yet known whether plant breeders will be able to improve the herbage quality of the perennial species without sacrificing some perenniality. Information needed to resolve this question could be obtained in various ways, some of which are discussed. Plant survival is of special importance in P. tuberosa, but in the ryegrasses some loss of perenniality has been tolerated by New Zealand farmers.

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Seasonal changes and the effect of temperature and leaf moisture content on intrinsic shear strength of leaves of pasture grasses

Australian Journal of Agricultural Research ◽

10.1071/ar98085 ◽

2000 ◽

Vol 51 (7) ◽

pp. 823 ◽

Cited By ~ 11

Author(s):

D. A. Henry ◽

R. J. Simpson ◽

R. H. Macmillan

Keyword(s):

Shear Strength ◽

Moisture Content ◽

Lignin Content ◽

Chemical Constituent ◽

Effect Of Temperature ◽

Green Leaves ◽

Dry Matter Digestibility ◽

Pasture Grasses

The intrinsic shear strength of leaves of 6 temperate pasture grasses was measured using a guillotine. The intrinsic shear strength of the leaves was represented as the force required to shear a leaf corrected for the length of cutting blade in contact with the material. When green leaves were maintained at 100% relative humidity, their moisture content was maintained and their intrinsic shear strength remained constant over a 24-h period. Shear strength increased when leaves were allowed to dehydrate. Shear strength varied significantly over a growing season, with strength generally higher in summer and lower in winter. When grown in a constant regime with day/night temperatures ranging from 14/6˚C to 34/26˚C, no consistent effects of temperature on shear strength were observed across species; however, higher temperatures did increase lignin content of the leaves and decreased in vitro dry matter digestibility. Any one chemical constituent of the leaves (e.g. lignin, cellulose) did not appear to contribute significantly to their strength. The intrinsic shear strength of senescent leaves of Phalaris aquatica was significantly higher than that of green leaves, but there was no correlation between the strength of green leaves and that of senescent leaves. Hence, mature forages during the summer period will exhibit increased intrinsic shear strength at a time of the year when the digestibility of the feed also declines and the quality of feed begins to limit animal production.

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Annotation: Class Size and the Quality of Educational Outcomes

Journal of Child Psychology and Psychiatry ◽

10.1017/s0021963098002819 ◽

1998 ◽

Vol 39 (6) ◽

pp. 797-804 ◽

Cited By ~ 8

Author(s):

Neville Bennett

Keyword(s):

Educational Outcomes ◽

Class Size

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Immunoferritin localization of intracellular antigens in positively stained frozen sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010008170x ◽

1978 ◽

Vol 36 (2) ◽

pp. 168-169

Author(s):

K. T. Tokuyasu

Keyword(s):

Surface Tension ◽

Water Surface ◽

Thin Layers ◽

The Other ◽

Positive Staining ◽

Frozen Sections ◽

The Past ◽

Ultrathin Frozen Sections ◽

Definition Of

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).

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Lithography below 100 nm

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100074367 ◽

1983 ◽

Vol 41 ◽

pp. 96-99

Author(s):

L. D. Jackel

Keyword(s):

Spatial Distribution ◽

Electron Beam ◽

Electron Scattering ◽

Electron Beam Lithography ◽

Substrate Material ◽

Local Electron ◽

Electron Dose ◽

Positive Resist ◽

Exposure Process

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.

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Convergent Beam Electron Diffraction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100070072 ◽

1978 ◽

Vol 36 (3) ◽

pp. 304-315

Author(s):

G. Lehmpfuhl

Keyword(s):

Electron Diffraction ◽

Diffraction Pattern ◽

Crystal Surface ◽

Diffraction Spot ◽

Crystal Thickness ◽

Large Area ◽

Electron Microscopic ◽

Additional Information ◽

Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

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